efi_loader: Do not leak memory when unlinking a mapping

As soon as a mapping is unlinked from the list, there are no further
references to it, so it should be freed. If it not unlinked,
update the s

efi_loader: Do not leak memory when unlinking a mapping

As soon as a mapping is unlinked from the list, there are no further
references to it, so it should be freed. If it not unlinked,
update the start address and length.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Alexander Graf <agraf@suse.de>

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efi_loader: Keep memory mapping sorted when splitting an entry

The code assumes sorted mappings in descending address order. When
splitting a mapping, insert the new part next to the current mapping

efi_loader: Keep memory mapping sorted when splitting an entry

The code assumes sorted mappings in descending address order. When
splitting a mapping, insert the new part next to the current mapping.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Alexander Graf <agraf@suse.de>

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efi_loader: Readd freed pages to memory pool

Currently each allocation creates a new mapping. Readding the mapping
as free memory (EFI_CONVENTIONAL_MEMORY) potentially allows to hand out
an existing

efi_loader: Readd freed pages to memory pool

Currently each allocation creates a new mapping. Readding the mapping
as free memory (EFI_CONVENTIONAL_MEMORY) potentially allows to hand out
an existing mapping, thus limiting the number of mapping descriptors in
the memory map.

Mitigates a problem with current (4.8rc7) linux kernels when doing an
efi_get_memory map, resulting in an infinite loop. Space for the memory
map is reserved with allocate_pool (implicitly creating a new mapping) and
filled. If there is insufficient slack space (8 entries) in the map, the
space is freed and a new round is started, with space for one more entry.
As each round increases requirement and allocation by exactly one, there
is never enough slack space. (At least 32 entries are allocated, so as
long as there are less than 24 entries, there is enough slack).
Earlier kernels reserved no slack, and did less allocations, so this
problem was not visible.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Alexander Graf <agraf@suse.de>

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efi_loader: Track size of pool allocations to allow freeing

We need a functional free_pool implementation, as otherwise each
allocate_pool causes growth of the memory descriptor table.

Different to

efi_loader: Track size of pool allocations to allow freeing

We need a functional free_pool implementation, as otherwise each
allocate_pool causes growth of the memory descriptor table.

Different to free_pages, free_pool does not provide the size for the
to be freed allocation, thus we have to track the size ourselves.

As the only EFI requirement for pool allocation is an alignment of
8 bytes, we can keep allocating a range using the page allocator,
reserve the first 8 bytes for our bookkeeping and hand out the
remainder to the caller. This saves us from having to use any
independent data structures for tracking.

To simplify the conversion between pool allocations and the corresponding
page allocation, we create an auxiliary struct efi_pool_allocation.

Given the allocation size free_pool size can handoff freeing the page
range, which was indirectly allocated by a call to allocate_pool,
to free_pages.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Alexander Graf <agraf@suse.de>

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efi_loader: Move efi_allocate_pool implementation to efi_memory.c

We currently handle efi_allocate_pool() in our boot time service
file. In the following patch, pool allocation will receive addition

efi_loader: Move efi_allocate_pool implementation to efi_memory.c

We currently handle efi_allocate_pool() in our boot time service
file. In the following patch, pool allocation will receive additional
internal semantics that we should preserve inside efi_memory.c instead.

As foundation for those changes, split the function into an externally
facing efi_allocate_pool_ext() for use by payloads and an internal helper
efi_allocate_pool() in efi_memory.c that handles the actual allocation.

While at it, change the magic 0xfff / 12 constants to the more obvious
EFI_PAGE_MASK/SHIFT defines.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Alexander Graf <agraf@suse.de>

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efi_loader: Fix crash on 32-bit systems

A type mismatch in the efi_allocate_pool boot service flow causes
hazardous memory scribbling on 32-bit systems.

This is efi_allocate_pool's prototype:

stat

efi_loader: Fix crash on 32-bit systems

A type mismatch in the efi_allocate_pool boot service flow causes
hazardous memory scribbling on 32-bit systems.

This is efi_allocate_pool's prototype:

static efi_status_t EFIAPI efi_allocate_pool(int pool_type,
unsigned long size,
void **buffer);

Internally, it invokes efi_allocate_pages as follows:

efi_allocate_pages(0, pool_type, (size + 0xfff) >> 12,
(void*)buffer);

This is efi_allocate_pages' prototype:

efi_status_t efi_allocate_pages(int type, int memory_type,
unsigned long pages,
uint64_t *memory);

The problem: efi_allocate_pages does this internally:

*memory = addr;

This fix in efi_allocate_pool uses a transitional uintptr_t cast to
ensure the correct outcome, irrespective of the system's native word
size.

This was observed when bootefi'ing the EFI instance of FreeBSD's first
stage bootstrap (boot1.efi) on a 32-bit ARM platform (Qemu VExpress +
Cortex-a9).

Signed-off-by: Robin Randhawa <robin.randhawa@arm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>

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efi_loader: Fix memory map size check to avoid out-of-bounds access

The current efi_get_memory_map() function overwrites the map_size
property before reading its value. That way the sanity check whe

efi_loader: Fix memory map size check to avoid out-of-bounds access

The current efi_get_memory_map() function overwrites the map_size
property before reading its value. That way the sanity check whether our
memory map fits into the given array always succeeds, potentially
overwriting arbitrary payload memory.

This patch moves the property update write after its sanity check, so
that the check actually verifies the correct value.

So far this has not triggered any known bugs, but we're better off safe
than sorry.

If the buffer is to small, the returned memory_map_size indicates the
required size to the caller.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Alexander Graf <agraf@suse.de>

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efi_loader: Update description of internal efi_mem_carve_out

In 74c16acce30bb882ad5951829d8dafef8eea564c the return values where
changed, but the description was kept.

Signed-off-by: Stefan Brüns <

efi_loader: Update description of internal efi_mem_carve_out

In 74c16acce30bb882ad5951829d8dafef8eea564c the return values where
changed, but the description was kept.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Alexander Graf <agraf@suse.de>

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arm: Add return value argument to longjmp

The normal longjmp command allows for a caller to pass the return value
of the setjmp() invocation. This patch adds that semantic to the arm
implementation

arm: Add return value argument to longjmp

The normal longjmp command allows for a caller to pass the return value
of the setjmp() invocation. This patch adds that semantic to the arm
implementation of it and adjusts the efi_loader call respectively.

Signed-off-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Simon Glass <sjg@chromium.org>

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efi_loader: provide efi_mem_desc version

Provide version of struct efi_mem_desc in efi_get_memory_map().

EFI_BOOT_SERVICES.GetMemoryMap() in UEFI specification v2.6 defines
memory descriptor versio

efi_loader: provide efi_mem_desc version

Provide version of struct efi_mem_desc in efi_get_memory_map().

EFI_BOOT_SERVICES.GetMemoryMap() in UEFI specification v2.6 defines
memory descriptor version to 1. Linux kernel also expects descriptor
version to be 1 and prints following warning during boot if its not:

Unexpected EFI_MEMORY_DESCRIPTOR version 0

Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@gmail.com>

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